Added names for mocks (#339)

Author: tochilinak

usvm-core/src/main/kotlin/org/usvm/Context.kt

@@ -366,9 +366,10 @@ open class UContext<USizeSort : USort>(
     private var trackedIndex = 0
 
     fun <Sort : USort> mkTrackedSymbol(
-        sort: Sort
+        sort: Sort,
+        name: String? = null,
     ): UTrackedSymbol<Sort> = trackedSymbols.createIfContextActive {
-        UTrackedSymbol(this, name = "tracked#${trackedIndex++}", sort)
+        UTrackedSymbol(this, name = "${name ?: "tracked"}#${trackedIndex++}", sort)
     }.cast()
 
     private val isSubtypeExprCache = mkAstInterner<UIsSubtypeExpr<Any>>()

usvm-core/src/main/kotlin/org/usvm/Mocks.kt

@@ -14,7 +14,9 @@ interface UMockEvaluator {
     fun <Sort : USort> eval(symbol: UMockSymbol<Sort>): UExpr<Sort>
 }
 
-interface TrackedLiteral
+interface TrackedLiteral {
+    val name: String
+}
 
 interface UMocker<Method> : UMockEvaluator {
     fun <Sort : USort> call(
@@ -69,7 +71,7 @@ class UIndexedMocker<Method>(
         sort: Sort,
         ownership: MutabilityOwnership,
     ): UExpr<Sort> {
-        val const = sort.uctx.mkTrackedSymbol(sort)
+        val const = sort.uctx.mkTrackedSymbol(sort, trackedLiteral?.name)
 
         if (trackedLiteral != null) {
             trackedSymbols = trackedSymbols.put(trackedLiteral, const, ownership)

usvm-core/src/main/kotlin/org/usvm/api/MockApi.kt

@@ -1,6 +1,7 @@
 package org.usvm.api
 
 import org.usvm.StepScope
+import org.usvm.TrackedLiteral
 import org.usvm.UBoolExpr
 import org.usvm.UExpr
 import org.usvm.UHeapRef
@@ -12,10 +13,11 @@ import org.usvm.utils.logAssertFailure
 // TODO: special mock api for variables
 
 fun <Method, T : USort> UState<*, Method, *, *, *, *>.makeSymbolicPrimitive(
-    sort: T
+    sort: T,
+    trackedLiteral: TrackedLiteral? = null,
 ): UExpr<T> {
     check(sort != sort.uctx.addressSort) { "$sort is not primitive" }
-    return memory.mocker.createMockSymbol(trackedLiteral = null, sort, ownership)
+    return memory.mocker.createMockSymbol(trackedLiteral = trackedLiteral, sort, ownership)
 }
 
 fun <Type, Method, State> StepScope<State, Type, *, *>.makeSymbolicRef(